Mesonormalization

Mesonormalization is a term used in theoretical physics to denote the set of conventions and procedures used to normalize meson states within quantum field theory. The term combines “meson” and “normalization” and is sometimes used to describe how the probabilistic interpretation of meson wavefunctions is preserved across different representations, such as covariant Bethe-Salpeter amplitudes, light-front wavefunctions, and lattice correlators.

In relativistic descriptions, mesons are bound states of a quark and an antiquark, so their state vectors must be normalized according to the chosen formalism. Covariant normalization typically enforces a delta-function normalization in momentum space, while light-front normalization uses the plus component of the momentum and specific Jacobians. Lattice QCD normalization relies on matching two-point functions to physical observables like decay constants.

Key quantities tied to meson normalization include the decay constant f_M, the normalization of the Bethe-Salpeter amplitude, and the normalization of light-front wavefunctions. These ensure that matrix elements of currents yield correct physical decay rates and form factors. Mesonormalization also involves renormalization-scale and scheme choices when defining distribution amplitudes and parton densities.

Challenges arise from scheme dependence, nonperturbative dynamics, and gauge invariance. Proper normalization is essential for reliable extraction of observables from theory-to-experiment comparisons, such as decay widths, transition form factors, and cross sections involving mesons.

See also: Normalization, Meson, Bethe-Salpeter equation, Lattice QCD, Decay constant, Light-front quantization.